Golfers often have difficulty properly aligning a putter club head with a golf ball along an intended direction of ball travel and accurately stroking the putter club head through the ball along the intended direction. If the putter is aligned and strikes the ball true, it will follow the laws of physics and move in the direction struck. It is critical to not only strike the center of the ball with the center of gravity of the putter, but also at the correct angle. Using the tangent formula, for every one degree of deviation from a perpendicular, a strike of the ball will be deviated approximately 0.209 inches per foot of travel. For a ten foot putt, this translates to 2.09 inches. Thus, performance can be improved by improving the alignment of the putter with the ball.
Vernier acuity in visual psychophysics refers to the process of identifying offset in parallel lines or dots. It is known that humans are remarkably adept at performing a vernier acuity task. Thresholds of vernier acuity are on the order of detecting approximately 10-30 seconds of arc. This threshold is approximately ten times better than any other type of acuity task, such as recognition acuity. Accordingly, a putting system that incorporates a vernier acuity task will assist the user in aligning a putt.
The contents of the following are herein incorporated by reference: How Vernier Acuity Depends on Contrast, Experimental Brain Research, C. Wehrhahn & G. Westheimer (1990); Sensation and Perception, J. M. Wolfe, K. Kluender, D. M. Levi, L. M. Bartoshuk, R. Herz, & R. Klatzky (2008); Temporal and Spatial Interference with Vernier Acuity, Vision Research, G. Westheimer & G. Hauske (1975); Development of VEP Vernier Acuity and Grating Acuity in Human Infants, Invest Ophthalmol Vis. Sci., Skoczenski & Norcia (September 1999); Contrast Polarity, Chromaticity, and Stereoscopic Depth Modulate Contextual Interactions in Vernier Acuity, Journal of Vision, B. Sayim, G. Westheimer & M. Herzog (2008); Visual Acuity and Spacial Modulation Thresholds, Handbook of Sensory Physiology Vol. 7, G. Westheimer (1972); and Visual Acuity, Adler's Physiology of the Eye, G. Westheimer (1987).